Question

Bỏ dấu ngoặc rồi tính:

-(a+b+c)-(a-b+c)-(a+b)

Answer 1

= -a - b - c - a + b - c - a - b

= (-a - a - a) + (-b + b - b) + (-c - c)

= -3a - b - 2c

 

Answer 2

-(a+b+c)-(a-b+c)-(a+b)

= -a-b-c -a+b-c-a-b

Answer 3

- (a+b+c) - (a-b-c) - (a+b) = - a - b - c - a + b + c - a - b

                                     = ( b - b ) + (  c - c ) - a - a - a - b

                                     = 0 + 0 - 3 ( - a ) - b

                                     = 3 ( - a ) -b

Answer 4

=-a-b-c-a+b-c-a-b

=(-a+a)+(-b+b)-c-a-b

=0+0-c-a-b=-c-a-b

 

Answer 5

-(a+b+c)-(a-b+c)-(a+b)

=-a-b-c-a+b-c-a-b

=(-a-a-a)+(-b+b-b)+(-c-c)

=-3a-b-2c

tick nha